From The Public Domain Movie Database:
Betty Boops efforts to stay in shape backfire when she becomes entangled in the exercise equipment. Jimmy seeks help for Betty, but becomes easily confused. In the meantime, Betty is becoming skinnier by the minute!
July 12, 2019 Subject:
Betty Normal, Small And Large
A weird one - first the Fleischers get around the Hayes Code, giving Betty skimpy form-fitting exercise togs. Then they get a shimmy dance courtesy of a weight-reducing belt vibrating machine. Then Little Jimmy, her gratuitous companion for this cartoon, shifts the machine into high gear and Betyy shakes uncontrollably while Little Jimmy goes off to find an electrician, no, a magician, no, a politician.... When hr grts back home, he pulls the cord, the machine stops - and too weird - we have an anorexic Betty - all the exercise machines and the furniture laugh -as does Betty and Jimmy - laugh so much that they take on a lot of air and get - weirder - very fat - and as we leave them, they are laughing themselves into immensity. Clever but weird.